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with bordeaux mixture, beginning soon after the fruits have set, and 
before the trouble begins to show. 
The fruit-rot may be prevented by the same means — that is, by 
spraying with bordeaux mixture. It is usually best to begin just after 
the fruits are well set. A very important consideration in the checking 
of this disease is to thin the fruit so that it does not hang in clusters. 
If one fruit touches another, the rot spreads from fruit to fruit in spite 
of the spraying. Some varieties, as Lombard and Abundance, are 
specially susceptible to this injury. 
The black-knot is best kept in check by cutting out the knots when- 
ever they can be seen, and burning them. As soon as the leaves drop, 
the orchard should be gone over and all knots taken out. Orchards 
that are thoroughly sprayed with bordeaux mixture for the leaf- 
blight and fruit-rot fungus are less liable to attacks of black-knot. 
The curculio, or the insect which is the parent of the worms in the 
fruit, is the inveterate enemy of the plum and other stone fruits. The 
mature beetle lays the eggs in the fruits when they are very small, 
usually beginning its work about as soon as the flowers fall. These 
eggs soon hatch, and the little maggot bores into the fruit. Those 
fruits that are attacked whilst very young ordinarily fall from the 
tree, but those attacked when they are half or more grown, may 
adhere to the tree, but remain wormy and gummy at the picking time. 
The mature beetles are sluggish in the mornings, and are easily jarred 
from the trees. Taking advantage of this fact, the fruit-grower may 
jar them on sheets; or, in large orchards, into a large canvas hopper, 
which is wheeled from tree to tree upon a wheelbarrow-like frame, and 
under the apex of which is a tin can into which the insects roll. There 
is a slit or opening in one side of the hopper, which allows the tree to 
stand nearly in the middle of the canvas. The operator then gives the 
tree two or three sharp jars with a padded pole or mallet. The edges of 
the hopper are then quickly shaken with the hands and the insects roll 
down into the tin receptacle. In this receptacle there is kerosene oil, 
or it may be emptied from time to time. Just how long this machine 
is to be run in the orchard will depend entirely on circumstances. It is 
advisable to use the catcher soon after the blossoms fall, for the purpose 
of finding out how abundant the insects are. If a few insects are 
caught from each tree, there is indication that there are enough of the 
